/*
    Hurry Curry! - a game about cooking
    Copyright 2024 metamuffin

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, version 3 of the License only.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.

*/
use crate::server::Server;
use anyhow::Result;
use get_if_addrs::get_if_addrs;
use hurrycurry_protocol::VERSION;
use log::{info, warn};
use mdns_sd::{ServiceDaemon, ServiceInfo};
use rand::random;
use std::{collections::HashMap, net::SocketAddr, sync::Arc, time::Duration};
use tokio::{sync::RwLock, time::interval};

pub async fn mdns_loop(name: String, listen_addr: SocketAddr, state: Arc<RwLock<Server>>) {
    let d = match ServiceDaemon::new() {
        Ok(d) => d,
        Err(e) => {
            warn!("mDNS daemon failed to start: {e}");
            return;
        }
    };
    let mut interval = interval(Duration::from_secs(60));
    let hostname = format!("hks-{}.local.", random::<u64>());
    loop {
        interval.tick().await;
        if let Err(e) = update_service(&d, &state, &name, &hostname, listen_addr).await {
            warn!("mDNS service update failed: {e}");
        }
        info!("updated mDNS service record");
    }
}

async fn update_service(
    d: &ServiceDaemon,
    state: &Arc<RwLock<Server>>,
    name: &str,
    hostname: &str,
    listen_addr: SocketAddr,
) -> Result<()> {
    let addrs = get_if_addrs()?
        .into_iter()
        .map(|e| e.addr.ip())
        .filter(|a| !a.is_loopback())
        .filter(|a| {
            (a.is_ipv6() && listen_addr.is_ipv6())
                || (a.is_ipv4() && listen_addr.is_ipv4())
                || (a.is_ipv4() && listen_addr.is_ipv6() && !cfg!(windows))
        })
        .collect::<Vec<_>>();

    let players = state.read().await.count_chefs();

    d.register(ServiceInfo::new(
        "_hurrycurry._tcp.local.",
        name,
        hostname,
        &*addrs,
        listen_addr.port(),
        HashMap::from_iter([
            ("players".to_string(), players.to_string()),
            ("version".to_string(), env!("CARGO_PKG_VERSION").to_string()),
            (
                "protocol".to_string(),
                format!("{}.{}", VERSION.0, VERSION.1),
            ),
        ]),
    )?)?;
    Ok(())
}